(Chris Hallbeck/Minimumble)Those are the best dreams ever because at least there's a chance that they will come true. It's only a small chance though--just enough to make you think that this morning it could happen....

This unusual clock is a solar cannon. It's a sundial that fires a tiny cannon when the heat of sunlight, concentrated wih a lens, detonates gunpowder. In a 1903 treatise on solar energy, Charles Henry Pope wrote:In the i...